Where does “tertiäärikausi” come from?
tertiäärikausi (Finnish) comes from Finnish tertiääri, from Swedish tertiär, from Latin tertiārius, from Latin tertius, from Latin trēs, from Proto-Italic trēs, from Proto-Indo-European *tréyes.
tertiäärikausi (Finnish): Tertiary
Ancestry of “tertiäärikausi”, step by step